Flea Bites / itchy Skin ?

I know that when a flea bite you, it itches on that spot, right? What if the bite was only on your thigh, knee, chest, and right arm(4 bites counting in total). The one on the right arm and knee itches like a mosquito bite and has grown to look like a mosquito bite but was not bitten by a mosquito. But the one on the chest and thigh does not itch, can somone explain that?

Also, is it normal if other parts of your body itch constantly. For example, your back, behind your thigh, behind your kneecaps, both legs, buttucks, and head? AND it does not itch like mosquito bites, it itches like a sharp sewing needle is poking you constantly and when you rub(not scratch) it--it goes away but 2-3 seconds later it comes back constantly. It lasts for about 2-3 hours. Is that related to flea bites?......The thing is that in those areas there are NO indication of bites, it just looks normal but it itches like crazy.

I should point out that when the needle like itching occurs and when I put a blanket over the area that's itching or put my palm over it the itching goes away which is weird. As far as taking showers nothing has changed-never used different soap and have always used the same ones. Please post asap, I thank you for your time.